Numerous techniques have been heretofore been devised for vending a wide variety of products by means of sequentially dropping a series of shelves causing the contents thereof to be dropped and guided or conveyed out to the customer. The resultant machines have generally been quite satisfactory from an operational stand point but frequently have not been economically feasable due to the length of time required for service and loading. This is generally recognized by those skilled in the art. U.S. Pat. No. 3,946,846 Pepiciello recognizes this need and teaches a means for minimizing the service cycle. To wit: the use of a "pivotably mounted master dog rotatable between an actuation position and a reset position" to facilitate the resetting of the shelf drop mechanism without disturbing those shelves which are still loaded and ready to vend. While of substantial value in its time it did make no provision for the rapid resetting of the shelves themselves. With many machines this can be an even greater time consuming function than the resetting of the shelf drop mechanism.
The present invention is in part a significant symplification of the Pepiciello system in that it teaches the use of an extended roller chain link pin as an actuator for dropping the shelves and a shelf supporting pawl or dog of such configuration that it does not obstruct but rather guides said actuator during the resetting cycle. In addition it also teaches the use of a lever controlled linkage to reset the empty shelves without materially disturbing the loaded ones. This shelf resetting means does result in a substantial saving when the service person has a large number of machines to service in a short period of time such as in the newspaper industry or, in machines where the shelves are not easy to reach and reset on a one at a time basis.
The detailed description of the moving parts and their function in the above mentioned patent attests to the fact that the simplicity of the present invention's actuator and pawls was neither suggested nor anticipated. Neither the above mentioned nor U.S. Pat. No. 464,067 Foster, 1,256,071 Steiner, or 2,904,216 Poland suggest nor anticipate the present rapid shelf resetting means.